This invention pertains to a pneumatically powered, combustion-powered, or other rapidly acting, fastener-driving tool of a type utilizing collated fasteners, as exemplified by a portable, pneumatically powered, nail-driving tool employing collated nails.
Typically, a fastener-driving tool of the type noted above comprises a housing structure including a handle and having a nosepiece, which defines a drive track adapted to receive a fastener and to guide the fastener as the fastener is driven from the drive track into a workpiece. Moreover, a piston and cylinder mechanism of the fastener-driving tool includes a driver, which is mounted for reciprocal movement along the drive track so as to be explosively driven by compressed air, by products of combustion, or otherwise from a retracted position to an extended position in a driving stroke, and so as to be oppositely driven by a return spring, by partial vacuum, or by other known means in a return stroke.
Typically, in such a tool, a magazine mounted to the housing structure is adapted to store a strip of collated fasteners, as exemplified by a strip of collated nails with a coiled portion stored in the magazine, so that a leading portion of the strip extends from the magazine toward the drive track. If the fasteners are nails, the nails may be conventionally collated by a pair of wires welded to one side of the nails.
It is known to provide means including a fastener-feeding element, such as a pawl, which has a groove or grooves adapted to receive one such fastener, for feeding fasteners individually and sequentially into the drive track from the leading portion of a given strip of collated fasteners. The fastener received by the groove or grooves of the fastener-feeding element constitutes a second fastener of such portion after a first fastener of such portion has been received by the drive track and before the first fastener has been driven from the drive track.
It is known also to provide a hinged cover, which is hinged to the housing structure, or to the magazine, so as to be hingedly movable between an operative position and inoperative positions, along with means for securing the hinged cover releasably in the operative position. In operative positions, the hinged cover is moved away so as to expose any fasteners between the magazine and the fastener-feeding element, whereby a jammed fastener can be then cleared from the drive track or a new strip of such fasteners can be then loaded.
Mukoyama U.S. Pat. No. 4,600,135 exemplifies such a tool, in which the hinged cover is integral with movable wall portions of the magazine and is hinged to the nosepiece. Fisher U.S. Pat. No. 3,708,097 exemplifies such a tool, in which the hinged cover is separate from the magazine and is hinged to the nosepiece; see, also, Colechia et al. U.S. Pat. No. 3,330,462.
It also is known to provide, in a fastener-driving tool having such a cover hinged to the magazine on an axis spaced from the nosepiece, a hinged latch, which is hinged to the nosepiece, and which is bolted into an operative position wherein the hinged latch is adapted to latch the hinged cover in an operative position. When unbolted, the hinged latch can be hingedly moved away so as to expose the drive track and fastener-feeding pawl of the fastener-driving tool, which cannot be then operated until the hinged latch has been rebolted.
A troublesome problem with many such tools, as known heretofore, is that the nail or other fastener received by the groove or grooves of the fastener-feeding element of such a tool tends to be easily dislodged from such groove or grooves as the hinged cover is moved to its operative position, e.g., after a jammed fastener has been cleared or after a new strip has been loaded. Consequently, the dislodged fastener can become another jammed fastener, which needs to be then cleared, or the hinged cover cannot be then moved to its operative position.